Nintendo kind of did this back in the day with the e-Reader accessory for the Game Boy Advance. It used dot-based "barcodes" to encode NES games onto cards that

Nintendo kind of did this back in the day with the e-Reader accessory for the Game Boy Advance. It used dot-based "barcodes" to encode NES games onto cards that you scanned and subsequently played from RAM. I imagine that some deft compression and the ARM Thumb instruction set came especially in handy here.